Note 2 - Cash, Cash Equivalents and Marketable Investments (Tables)

3 Months Ended

Mar. 31, 2017

Notes Tables

Unrealized Gain (Loss) on Investments [Table Text Block]

March 3 1 , 201 7	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Market Value
Cash and cash equivalents:
Cash	$	6,918	$	—	$	—		$	6,918
Money market funds		1,026		—		—			1,026
Commercial paper		3,499		—		—			3,499
Total cash and cash equivalents		11,443		—		—			11,443
Marketable investments:
U.S. government notes		4,453		—		(11	)		4,442
U.S. government agencies		2,002		—		(2	)		2,000
Municipal securities		—		—		—			—
Commercial paper		17,243		3		(1	)		17,245
Corporate debt securities		13,305		7		(9	)		13,303
Total marketable investments		37,003		10		(23	)		36,990
Total cash, cash equivalents and marketable investments	$	48,446	$	10	$	(23	)	$	48,433

December 31, 2016	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Market Value
Cash and cash equivalents:
Cash	$	6,672	$	—	$	—		$	6,672
Money market funds		6,053		—		—			6,053
Commercial paper		1,050		—		—			1,050
Total cash and cash equivalents		13,775		—		—			13,775
Marketable investments:
U.S. government notes		8,403		4		(9	)		8,398
U.S. government agencies		3,918		—		(2	)		3,916
Municipal securities		1,325		—		—			1,325
Commercial paper		12,299		2		(2	)		12,299
Corporate debt securities		14,366		3		(8	)		14,361
Total marketable investments		40,311		9		(21	)		40,299
Total cash, cash equivalents and marketable investments	$	54,086	$	9	$	(21	)	$	54,074

Investments Classified by Contractual Maturity Date [Table Text Block]

	Amount
Due in less than one year	$	33,230
Due in 1 to 3 years		3,760
Total marketable investments	$	36,990